| amide linkage | <biochemistry> This is a carboxylic acid containing an amino group (-NH2). In an alpha amino acid, the amino group is attached to the carbon atom directly beside the carboxyl group. (09 Oct 1997) |
|---|---|
| atomic | 1. Of or pertaining to atoms. 2. Extremely minute; tiny. Atomic philosophy, or Doctrine of atoms, a system which assuming that atoms are endued with gravity and motion accounted thus for the origin and formation of all things. This philosophy was first broached by Leucippus, was developed by Democritus, and afterward improved by Epicurus, and hence is sometimes denominated the Epicurean philosophy. <chemistry> Atomic theory, or the Doctrine of definite proportions, the weight of the atom of an element as compared with the weight of the atom of hydrogen, taken as a standard. Origin: Cf. F. Atomique. Source: Websters Dictionary (01 Mar 1998) |
| atomic absorption spectrophotometry | Determination of concentration by the ability of atoms to absorb radiant energy of specific wavelengths. (05 Mar 2000) |
| atomic bomb | <physics, radiobiology> A weapon with a large explosive power due to the sudden release of energy when the nuclei of heavy atoms such as plutonium-239 or uranium-235 are split. This fission is brought about by the bombardment of the fuel with neutrons, setting off a chain reaction. The bomb releases shock, blast, heat, light, and lethal radiation. The world's first atomic bomb was successfully tested by the United States on July 16, 1945. (13 Nov 1997) |
| atomic core | The nucleus plus the nonvalence electrons. (05 Mar 2000) |
| atomic heat | The amount of heat required to raise an atom from 0 |
| atomic mass | <chemistry, physics> The mass of an atom relative to other atoms. The present-day basis of the scale of atomic weights is carbon, the most common isotope of this element has arbitrarily been assigned an atomic weight of 12. The unit of the scale is 1/12 the weight of the carbon atom or roughly the mass of one proton or one neutron. The atomic weight of any element is approximately equal to the total number of protons and neutrons in is nucleus (16 Dec 1997) |
| atomic mass unit | <chemistry> One-twelfth the mass of a neutral atom of the most abundant isotope of carbon. (16 Dec 1997) |
| atomic number | <chemistry> Symbol Z. The number of protons in the nucleus of an atom and also its characteristic atomic number. The atomic numbers of the known elements form a complete series from 1 (hydrogen) to 103 (lawrencium). (16 Dec 1997) |
| atomic theory | That chemical compounds are formed by the union of atoms in certain definite proportions; in its modern form, first advanced in 1803 by John Dalton. (05 Mar 2000) |
| atomic volume | The atomic weight of an element divided by its density in the solid state; the volume of the gram-atomic weight of a solid element. (05 Mar 2000) |
| atomic weight | <chemistry> The average weight of an atom of an element, i.e. The total mass of protons and neutrons in an atom. (09 Oct 1997) |
| map, linkage | A map of the genes on a chromosome based on linkage analysis. A linkage map does not show the physical distances between genes but rather their relative positions, as determined by how often two gene loci are inherited together. The closer two genes are (the more tightly they are linked), the more often they will be inherited together. Linkage distance is measured in centimorgans (cm). (12 Dec 1998) |
| genetic linkage | <genetics> The term refers to the fact that certain genes tend to be inherited together, because they are on the same chromosome. Thus parental combinations of characters are found more frequently in offspring than nonparental. Linkage is measured by the percentage recombination between loci, unlinked genes showing 50% recombination. See: linkage equilibrium, linkage disequilibrium. (18 Nov 1997) |
| glucosidic linkage | <biochemistry> The linkages between dextrose molecules in a glucoside compound which must be hydrolysed (broken apart) to produce the dextrose molecules. (09 Oct 1997) |